It's as if the sudoku puzzle has overtaken the humble crossword as the pastime of choice almost overnight. I mean it was only a couple of years ago that if I had said "sudoku" to most people, they would have thought I was talking about a brand of tyres or a new sushi restaurant. It seems that some people have become so addicted to the phenomena, that they find that they must solve sudoku puzzles on their PC's as well as on the train to work, whilst jogging in the park, attending important business meetings and taking their wedding vows.

If you fall into the category above, then you should probably seek some sound medical advice - but before you do - check out Pure Sudoku Deluxe by Mochek Interactive. This compact and functional application will let you solve over 20,000 sudoku puzzles right there on your PC.

I didn't believe the blurb on the website and did the math for myself. At the rate of one puzzle a day, that's enough to keep you going for well over 50 years! That wasn't enough though, I needed to know how much each puzzle cost. Let's face it, you can buy a book of sudoku puzzles at your local newsagent for the price of a cup of coffee. About 5 minutes of arithmetic later (math not one of my strong points), I came to the astounding conclusion that this equates to just 0.05 US cents per puzzle. How can you not afford to buy Pure Sudoku Deluxe?

OK, I've padded this review out enough. Let's get down to the nuts and bolts. The gameboard looks typically like the screenshot to the left. The full version of the game features 150 photograhs which are chosen at random to appear as the backdrops. Cuddly rabbits to scenic sunsets to Stonehenge and everything in between.

Though some of the darker coloured backdrops can make the smaller numbers on the board a bit hard to see, this is not a major problem since you can just save and reload to get a new picture. The backdrops keep the gameboard colourful and fresh. Fonts are large and clear. The game can be played in full screen mode for even more comfortable play or in a window so that you can whip out a spreadsheet when you see the boss approaching your cubicle.

The interface seemed logical and intuitive to me. You simply click on one of the numbers from the column on the left and then either left click to add a solved number to the puzzle, or right click to add a notational small grey number that can be used to indicate possible solutions for a particular cell. The delete button is right there at the top if you need to take a deep breath and erase certain cells. However, an undo function might have been welcomed for those stray right mouse clicks whilst moving the cursor that I seemed to perfect.

Puzzles can be printed on to plain paper so that you can take them on holidays with you, and this applies to partially completed ones too (that's the puzzles, by the way, not the holidays). There's even a help section that will teach you the basics of sudoku puzzles if you are one of the 347 people left on Earth not to know about them.

There is no in-game music, which is not a drawback in my opinion, and sounds are kept to some very basic clicks and beeps, although you do get the obligatory cheers and applause upon completion of a puzzle.

Puzzles come in 5 levels of difficulty with the 3rd level generating a game that I could clear in about 20 to 30 minutes. For the record I am a capable yet by no means an expert sudokist. (Hey, I just invented a word!)

Pure Sudoku Deluxe will not wash the dishes, remember your loved ones birthdays, or get you out of paying parking fines. It will allow you to solve sudoku puzzles on your PC, and judging by the sheer popularity of those at the moment, I'm guessing that the market is there for such a thing.